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| 06/13/18

Watering down an already diluted aviation emissions pact


European countries are pushing back against attempts at weakening the rules governing the first global pact on aviation emissions. But even if successful, these states themselves are finding aviation just dang hard to decarbonize. We explain why.

Ahead of a Montreal meeting this week to hammer out the rulebook governing the first-ever global pact aimed at reducing greenhouse gas emissions from the aviation sector, a half dozen European countries warned they may pull out of the agreement due to efforts by developing countries to water down its already limited ambition.

In 2016, Canada took a lead role in corralling the 191 member states of the International Civil Aviation Organization (ICAO) into signing the agreement, which would cap emissions from international aviation at 2020 levels by 2027.

But in the last week, letters from European Union member states Austria, Belgium, Finland, France and the Netherlands, and non-EU nation Norway were leaked to a Brussels-based green transport NGO, Transport & Environment, threatening to reconsider their support for the ICAO’s proposed Carbon Offset and Reduction Scheme for International Aviation (CORSIA). The countries are worried that the biofuels and offsets sustainability criteria have been weakened.

Originally there had been 12 criteria limiting what counts as a sustainable biofuel. That has been reduced down to two criteria: that biofuels not be produced on former forests or wetlands, and that they produce no more than 90 per cent of the emissions of their conventional jet fuel counterpart.

The European countries said that this is no longer robust enough to ensure their sustainability.

Even before the latest controversy, the pact came in for criticism from climate hawks for its embrace of biofuels and for depending primarily on the construction of a global aviation carbon offsets system to achieve this. In other words, paying for actors somewhere else in the economy to perform the emissions reduction for them.

Some offsets have been questioned over their rigour and long-term sustainability. Greater offset stringency has been introduced under some systems as a result, but at best, offsets only offer a bridge to real emissions reductions within the aviation sector itself. This is because at some point, every part of the economy has to eliminate 100 per cent of its emissions, and there will be no other actor in the economy that can balance out the carbon pollution of airplanes.

Beyond offsets, biofuels are expected to play a big role in the pact. But here too, many first-generation biofuels, which come from agricultural crops, have been shown to have worse emissions profiles than fossil fuels due in large part to land-use changes.

So if not via offsets or first-generation biofuels, what are the options for decarbonization of the aviation sector? It turns out that aviation is one of the most difficult parts of our economy to decarbonize, and this may be why so many countries and the industry itself is appearing to drag its feet compared to other sectors.

The Canadian government for its part has placed its bet on second-generation biofuels. These are produced from crop residues, forestry scraps and even household waste, and so do not compete for arable land with agriculture or lead to land-use changes. Via its Green Aviation Research and Development Network (GARDN) program, Ottawa has partnered with researchers and nationally-based airlines to trial a series of sustainable biofuel-only flights and is now looking to support wider efforts at scale.

The challenge here is that it is unlikely that second-generation jet biofuels will ever deliver the volumes needed by an industry that is currently responsible for 2.5 per cent of global emissions (Canada as a whole is responsible for 2 per cent), emissions that are set to increase by more than three quarters over the next two decades. Canadian-based international aviation emissions have climbed 85 per cent since 1990.

Electrification is another option, but the size and weight of batteries needed for long distances also limits the viability of electric planes beyond short-haul trips.

The EU and Airbus experimented with a third option. In the early 2000s, they funded the development of prototype hydrogen-fuelled planes, so-called “cryoplanes” due to the employment of cryogenic liquid hydrogen. But while the industry once touted the concept as its main climate solution, it has since abandoned the concept due to technical feasibility, safety, economic viability and even environmental challenges.

Due to the nature of flight, it is really hard to decarbonize aviation outside the development of what are called synthetic hydrocarbons, a.k.a. synfuels. This involves drawing down CO2 from the air via what is called “direct air capture” (DAC, sometimes called “artificial trees”). The captured CO2 is then combined with sustainably sourced hydrogen. When used by planes (or any other machine that runs on liquid fuel), synfuels return to the atmosphere the CO2 that had been captured by the artificial trees, and thus are carbon neutral. Yet as far as an internal combustion engine is concerned, they are identical to conventional gasoline or kerosene. This has the added bonus of not having to depend on new types of planes.

Yet even here, DAC and synfuels face development challenges that are similar to that of carbon capture and storage, another proposed climate mitigation solution for hard-to-decarbonize sectors. Here the barrier here is one of cost. Synfuel production remains eye-wateringly expensive. If there is some way of getting costs down sharply, then aviation decarbonization might be on to a winner.

In depth

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